BAE proposes GPS-less location Whether or not Iran used GPS spoofing to down a US drone last year, there’s no doubt that GPS spoofing is both real and easier than the military would like. Now, BAE Systems is proposing a positioning technology that works without GPS. The defence company says its NAVSOP system – Navigation via Signals of Oppurtunity – allows …
Or in a situation where terrestrial transmitters have been rendered useless - widespread power outage due to natural disaster or orchestrated attack on power infrastructure.
It strikes me that just the times when you NEed a decent, accurate, reliable system coincide with when this system won't work.
Might be fine for consumer positioning/navigation, but not as an outright replacement to the satellite system.
Presumably in the empty wastes of flashpointistan it can fall back on GPS, or cross reference with the array of broadcast satellites in geosynchronous orbit.
Actually with the number of known satellites up there you wonder if they need the GPS constellation anyway!*
*I'm being flippant, I know how GPS works to a boring degree.
Step one: flood airwaves jamming all monitored channels (2.4GHz etc)
Step two: Apply GPS spoof.
To use any satellite, Wifi router etc in a positioning solution you need a very good idea of (a) where it is and (b) its clocking.
If a new solution relies on, say, signal strengths of Wifi routers, then all Johnny Terrorist needs to do is mount a few Wifi routers on planes / trucks and move them around. That will confuse stuff.
They way I read it this system doesn't just use WiFi routers it uses all signals around it: mobile phone towers, TV/radio masts along with WiFi routers. Johnny Terrorist would need to spoof all of those too.
In any event this would only use known sources so even without the TV/radio and mobile phone sources he would need to clone all the routers along the targets assigned path and place them on his path of doom! (Along with shutting down all the original routers)
Not really, he just needs to stop them transmitting. On the mundane level, this is as simple as blowing them up, or blowing up the power lines, substations or power stations which run them. On the electronic level, you can jam them perfectly well. Sure this kit could use the jammer itself as a reference source, but a single jammer is a single-point source which doesn't let you triangulate (and it wouldn't be much use anyway unless you knew its location).
Plenty of companies have been looking at this type of positioning for years.
It helps that things like cell phone towers and digital TV signals have accurate time stamps meaning that you can do some time of flight calculations rather than using a pure signal strength position calculation, a huge accuracy boost.
And due to the angle and number of potential data sources the indoor position can be far better than with GPS.
But it has a few big downsides:
Due to the geometry of the signals height accuracy sucks.
It only works in areas where you have a good reliable database of signal source locations
And in the event of a big disaster/power outage the signals you are trying to locate from could well be unavailable.
So it only works reliably in friendly countries under non-emergency conditions.
In terms of spoofing it would be harder to spoof than civilian GPS due to the number and variety of potential positioning signals. But it would still be easier to fake using off the shelf parts than military GPS.
Is it a good positioning technology to use as an independent position verification or backup to GPS? Yes
Is it a replacement for GPS? No.
>Is it a replacement for GPS? No.
By definition, it can't replace GPS because it is the incorporation of GPS and every other signal it can receive over a wide spectrum. Its like asking if a full set of spanners can be a replacement for one 17mm spanner.
>And in the event of a big disaster/power outage the signals you are trying to locate from could well be unavailable.
You have other frequencies you can fall back on, LW, for example, which travel further distances. Having an accurate but imprecise idea of where you are is better than no idea, and will aid the system in making sense of other signals to increase precision over time.
It's my understanding that terrestrial transmitters can employ different, more-reliable timebases. American transmitters, for example, can rely on the NIST radio time beacon for a timebase. This is the timebases used for the clock signals stuffed into the VBI of American PBS stations, IIRC. Consumer devices can also tune into the NIST signal. In England, you have the MSF time beacon which performs the same role. Various other time beacons exist in the western world, and even China and Japan keep a time beacon running. In addition, terrestrial stations can employ terrestrial networks to help calibrate their clocks.
Isn't this called AGPS and currently used by mobile phones (though extending the signals used beyond phone masts and wifi).
Minor downside that it doesn't work without a data connection because you need a bloody big (and up to date) database to query your location against.
I also fail to see how this does not suffer from exactly the same problems as GPS regards spoofing.
>I also fail to see how this does not suffer from exactly the same problems as GPS regards spoofing.
Because to spoof this system you would have to spoof all other radio transmissions too. Imagine it triangulating a range of signals all the time, (building a database in real time) and then suddenly the GPS disagrees with everything else, including its gyroscopes...
It can also use a GPS-jamming itself as a reference point for navigation. Cheeky.
http://www.baesystems.com/article/BAES_053641/bae-systems-locates-opportunity-to-replace-gps
Even BAE's site says it can only use the GPS jamming signal under certain circumstances. It's a fair assumption GPS spoofing can't be used, and that under most realistic circumstances it can't be used at all (Mobile jammer? Jammer varies it's signal strength?). At the end of the day these guys are selling a product.
The technology is probably useless without the data uplink to HQ, and any GPS spoofing attack is probably going to attempt to jam the hell out of that anyway.
And yeh, it can always fall back to gyros, but then it can do that without this technology (Though the technology might be useful for identifying when to fall back to gyros, but then that isn't what they're saying it's capable of, hence my grumpy post).
BAE seem to claim it can even use mobile transmitters as reference points; LEO satellites in sparse polar regions. So not only is it direction finding and monitoring the received power (from a mobile platform, how? beam forming?), it's also working out the trajectory of moving transmitters (doppler shift between several observations?) and presumably discarding signals that can't be correlated with the majority. Sounds to me like a freaking awesome piece of kit.
I for one would like to see an open source version.
The flaw it has currently is that it needs a initial GPS signal to get it's bearings. Least thats how it is running in tests currently. For built up area's this will be wonderful, though there is a way easier way of doing this. Pulse encoded streetlights that flicker at a rate that is not noticable to us mear mortals and provides a unique ID for the location, this in itself will be useful for drivers who happen to use roads which have street lights. This of course is great for nighttime and less so during the day though. So you then look at just putting a wire in the middle of the road or updated cat's eye's with built in RFID's.
But this idea whilst not realy new, does need to have a process of mapping all those changes and if it relies upon WIFI and other sources that can move then there could be even more fun. I know when I moved my phone would think I was at my old address as poor old google hadn't driven past my new location and updated there records for my wifi signal and the onus was upon oneself to do that. This is were you start to create the kind of problems your trying to fix.
Still there is one thing you can be assured of, with all those radio dignals from various frequencies would need alot of areils and that will be interesting to not only see how apple implement it but also claim they invented it as they are a bunch of cnuts. There had to be said :0.
>I know when I moved my phone would think I was at my old address as poor old google hadn't driven past my new location and updated
Yeah, your phone can triangulate cell towers and obviously GPS birds... but if had been doing the same with FM, TV and a host of other transmissions, it would have enough to know that your WiFi- location was an aberration. Consider a missile would have inertial nav system too. Obviously this would take some software engineering, but easily possible.
>would need alot of areils and that will be interesting to not only see how apple implement it but also claim they invented it as they are a bunch of cnuts.
?! Who are cnuts? The shiny shiny consumer electronics company, or the people who make weapon systems that could help deliver mega-deaths? And how did Apple-bashing get on this thread?
There aren't as many holes as you suppose- the article doesn't mention tricks such as using the GPS-jammer itself as navigation aid.
If you imagine it constantly triangulating a range of frequencies and building a 'map' on the fly, you might see how it won't be so bothered by losing one means of determining its location, or how it can know if it is suddenly having its GPS spoofed.
Put like that, it only seem sensible and straightforward way of bringing redundancy to a device you really don't want to hit the ground in the wrong place- as that poor fella in S Korea who got killed by his own drone last week would surely agree.
The US scanning radio manufacturer offers a fully programmed radio (HP-1 "Home Patrol") that is not only able to accept location signals (from a GPS, not internally) or be programmed by name or postal code, but that can also tell where in the US or Canada one is and select the appropriate law and safety agency frequencies to tune in based on what frequencies it detects in use.
Back in the early days of broadband, I used to follow a forum for DSL geeks.
One chap was having problems with gaps in the frequencies his kit was able to use. Usually it's a fairly level(ish) spread but his had deep notches on specific frequencies.
By correlating the notch frequencies with the frequencies of UK medium wave radio stations (ADSL is radio down the telephone wires, as is VDSL), someone worked out the chap was probably somewhere in the east midlands, maybe Leicestershire.
They should have patented the idea there and then.
No, sorry BAe, on thinking about it, your idea is still rollocks (in the general case).
So, they've re-invented the old "Securicor DataTrak" system which was developed by the Royal Navy, and patented :
US5173710
Navigation and positioning system and method using uncoordinated beacon signals
Old old old. And it worked too! Maybe not as accurate as GPS is, but they can work on that I'm sure.
So there.
Inertial Nav has been around for years, yes you can screw the set up(*), but there is very little an opponent can do subsequently to screw with it.
(*) - see FAA Harrier Pilot of ZA176 for why he had to land on a container ship, much to the financial happiness of the container crew ($1m+ in salvage)
Sadly there is a lot of misinformation and guesswork about NAVSOP - New Scientist was the source for this article, and they didn't actually interview BAE they just speculated about NAVSOP and how it works and didn't know about some key aspects (NAVSOP doesn't use signal strength outside as a primary positioning aid, it exploits timing and carrier phase). See the explanations on slash dot and in "the engineer" magazine for more information and less guesswork.
http://www.theengineer.co.uk/sectors/electronics/news/bae-navigation-system-identifies-suspicious-signals/1013081.article
and
http://tech.slashdot.org/comments.pl?sid=2950387&cid=40517317
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